diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0ad0bcb..319c28d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - DEP: drop `[isolated]` extra (external tooling should handle dependency pinning)
 - BLD: drop package level `__version__` attribute
 - BLD: migrate build backend from `setuptools` to `hatchling`
+- RFC: refactor theme-handling internals
 
 ## [5.2.1] - 2024-09-20
 
diff --git a/pyproject.toml b/pyproject.toml
index 35b7b1d..225ddbc 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,8 +30,8 @@ file = "README.md"
 content-type = "text/markdown"
 
 [project.scripts]
-idfx = "idefix_cli.__main__:main"
-baballe = "idefix_cli.__main__:alt_main"
+idfx = "idefix_cli.__main__:idfx_entry_point"
+baballe = "idefix_cli.__main__:baballe_entry_point"
 
 [project.urls]
 Homepage = "https://github.com/neutrinoceros/idefix_cli"
diff --git a/src/idefix_cli/__main__.py b/src/idefix_cli/__main__.py
index 56a2abd..1dff546 100644
--- a/src/idefix_cli/__main__.py
+++ b/src/idefix_cli/__main__.py
@@ -1,15 +1,14 @@
 import inspect
 import os
 import sys
-import unicodedata
 from argparse import ArgumentDefaultsHelpFormatter, ArgumentParser
 from importlib.metadata import version
 from importlib.util import module_from_spec, spec_from_file_location
 from pathlib import Path
 from types import FunctionType, ModuleType
-from typing import Any, Final
+from typing import Any, Final, Literal
 
-from idefix_cli._theme import set_theme
+from idefix_cli._theme import theme_ctx
 from idefix_cli.lib import get_config_file, get_option, print_error, print_warning
 
 CommandMap = dict[str, tuple[FunctionType, bool]]
@@ -113,14 +112,10 @@ def _setup_commands(parser: ArgumentParser) -> CommandMap:
     return cmddict
 
 
-def main(
-    argv: list[str] | None = None,
-    parser: ArgumentParser | None = None,
-) -> Any:
+def cli(caller: Literal["idfx", "baballe"], argv: list[str] | None = None) -> Any:
     # the return value is deleguated to sub commands so its type is arbitrary
     # In practice it should be either 'int' or 'typing.NoReturn'
-    if parser is None:
-        parser = ArgumentParser(prog="idfx", allow_abbrev=False)
+    parser = ArgumentParser(prog=caller, allow_abbrev=False)
     parser.add_argument(
         "-v", "--version", action="version", version=version("idefix-cli")
     )
@@ -145,26 +140,20 @@ def main(
     return cmd(*unknown_args, **vars(known_args))
 
 
-def alt_main(argv: list[str] | None = None) -> Any:
-    print(
-        unicodedata.lookup("BASEBALL")
-        + unicodedata.lookup("BLACK RIGHT-POINTING TRIANGLE"),
-        file=sys.stderr,
-    )
+def main(caller: Literal["idfx", "baballe"], argv: list[str] | None = None) -> Any:
+    theme_name = {"idfx": "default", "baballe": "baballe"}[caller]
+
+    with theme_ctx(theme_name):
+        return cli(caller, argv)
+
+
+def idfx_entry_point(argv: list[str] | None = None) -> Any:
+    return main(caller="idfx", argv=argv)
 
-    set_theme("baballe")
-    try:
-        retv = main(argv, parser=ArgumentParser(prog="baballe", allow_abbrev=False))
-    finally:
-        set_theme("default")
-        print(
-            unicodedata.lookup("BLACK LEFT-POINTING TRIANGLE")
-            + unicodedata.lookup("BASEBALL"),
-            file=sys.stderr,
-        )
 
-    return retv
+def baballe_entry_point(argv: list[str] | None = None) -> Any:
+    return main(caller="baballe", argv=argv)
 
 
-if __name__ == "__main__":
-    sys.exit(main())
+if __name__ == "__main__":  # pragma: no cover
+    sys.exit(main(caller="idfx"))
diff --git a/src/idefix_cli/_theme.py b/src/idefix_cli/_theme.py
index fe54102..d4ab976 100644
--- a/src/idefix_cli/_theme.py
+++ b/src/idefix_cli/_theme.py
@@ -1,14 +1,13 @@
 import sys
 import unicodedata
+from contextlib import contextmanager
+from dataclasses import dataclass
 from typing import Literal, TypedDict
 
-if sys.version_info >= (3, 11):
-    from typing import assert_never
-else:
-    from typing_extensions import assert_never
+__all__ = ["get_symbol", "theme_ctx"]
 
 
-class Theme(TypedDict):
+class SymbolSet(TypedDict):
     LAUNCH: str
     SUCCESS: str
     WARNING: str
@@ -16,35 +15,81 @@ class Theme(TypedDict):
     HINT: str
 
 
-Default = Theme(
-    LAUNCH=unicodedata.lookup("ROCKET"),  # 🚀
-    SUCCESS=unicodedata.lookup("PARTY POPPER"),  # 🎉
-    WARNING=unicodedata.lookup("HEAVY EXCLAMATION MARK SYMBOL"),  # ❗
-    ERROR=unicodedata.lookup("COLLISION SYMBOL"),  # 💥
-    HINT=unicodedata.lookup("LEFT-POINTING MAGNIFYING GLASS"),  # 🔍
+@dataclass(frozen=True, slots=True, kw_only=True)
+class Theme:
+    name: str
+    symbols: SymbolSet
+    enter_msg: str | None
+    exit_msg: str | None
+
+
+class ThemeRegistry:
+    def __init__(self):
+        self._registry: dict[str, Theme] = {}
+
+    def register(
+        self,
+        name: str,
+        *,
+        symbols: SymbolSet,
+        enter: str | None = None,
+        exit: str | None = None,
+    ):
+        self._registry[name] = Theme(
+            name=name, symbols=symbols, enter_msg=enter, exit_msg=exit
+        )
+
+    def __getitem__(self, item: str) -> Theme:
+        return self._registry[item]
+
+
+themes = ThemeRegistry()
+themes.register(
+    name="default",
+    symbols={
+        "LAUNCH": unicodedata.lookup("ROCKET"),  # 🚀
+        "SUCCESS": unicodedata.lookup("PARTY POPPER"),  # 🎉
+        "WARNING": unicodedata.lookup("HEAVY EXCLAMATION MARK SYMBOL"),  # ❗
+        "ERROR": unicodedata.lookup("COLLISION SYMBOL"),  # 💥
+        "HINT": unicodedata.lookup("LEFT-POINTING MAGNIFYING GLASS"),  # 🔍
+    },
 )
 
-Baballe = Theme(
-    LAUNCH=unicodedata.lookup("GUIDE DOG"),  # 🦮
-    SUCCESS=unicodedata.lookup("POODLE"),  # 🐩
-    WARNING=unicodedata.lookup("PAW PRINTS"),  # 🐾
-    ERROR=unicodedata.lookup("HOT DOG"),  # 🌭
-    HINT=unicodedata.lookup("CRYSTAL BALL"),  # 🔮
+themes.register(
+    name="baballe",
+    symbols={
+        "LAUNCH": unicodedata.lookup("GUIDE DOG"),  # 🦮
+        "SUCCESS": unicodedata.lookup("POODLE"),  # 🐩
+        "WARNING": unicodedata.lookup("PAW PRINTS"),  # 🐾
+        "ERROR": unicodedata.lookup("HOT DOG"),  # 🌭
+        "HINT": unicodedata.lookup("CRYSTAL BALL"),  # 🔮
+    },
+    enter=unicodedata.lookup("BASEBALL")
+    + unicodedata.lookup("BLACK RIGHT-POINTING TRIANGLE"),
+    exit=unicodedata.lookup("BLACK LEFT-POINTING TRIANGLE")
+    + unicodedata.lookup("BASEBALL"),
 )
 
 
-THEME = Default
+THEME = themes["default"]
+
 
+def get_symbol(key: Literal["LAUNCH", "SUCCESS", "WARNING", "ERROR", "HINT"]) -> str:
+    return THEME.symbols[key]
 
-def set_theme(theme: Literal["default", "baballe"]) -> None:
+
+@contextmanager
+def theme_ctx(name: str):
     global THEME
-    if theme == "default":
-        THEME = Default
-    elif theme == "baballe":
-        THEME = Baballe
-    else:
-        assert_never(theme)
+    old_name = THEME.name
+    THEME = themes[name]
 
+    if THEME.enter_msg is not None:
+        print(THEME.enter_msg, file=sys.stderr)
+    try:
+        yield
+    finally:
+        if THEME.exit_msg is not None:
+            print(THEME.exit_msg, file=sys.stderr)
 
-def get_symbol(key: Literal["LAUNCH", "SUCCESS", "WARNING", "ERROR", "HINT"]) -> str:
-    return THEME[key]
+        THEME = themes[old_name]
diff --git a/tests/test_app_structure.py b/tests/test_app_structure.py
index 868c1dc..1368af8 100644
--- a/tests/test_app_structure.py
+++ b/tests/test_app_structure.py
@@ -7,7 +7,7 @@
 
 import pytest
 
-from idefix_cli.__main__ import _setup_commands, main
+from idefix_cli.__main__ import _setup_commands, idfx_entry_point as main
 from idefix_cli.lib import print_error
 
 
diff --git a/tests/test_clean.py b/tests/test_clean.py
index 1ef4336..ebb7b41 100644
--- a/tests/test_clean.py
+++ b/tests/test_clean.py
@@ -2,7 +2,7 @@
 
 import pytest
 
-from idefix_cli.__main__ import main
+from idefix_cli.__main__ import idfx_entry_point as main
 from idefix_cli._commands.clean import gpatterns, kokkos_files
 
 
diff --git a/tests/test_clone.py b/tests/test_clone.py
index 32d5477..275bf9a 100644
--- a/tests/test_clone.py
+++ b/tests/test_clone.py
@@ -3,7 +3,7 @@
 
 import pytest
 
-from idefix_cli.__main__ import main
+from idefix_cli.__main__ import idfx_entry_point as main
 
 DATADIR = Path(__file__).parent / "data"
 BASE_SETUP = DATADIR / "OrszagTang3D"
diff --git a/tests/test_conf.py b/tests/test_conf.py
index e6351ac..99b9e7f 100644
--- a/tests/test_conf.py
+++ b/tests/test_conf.py
@@ -4,7 +4,7 @@
 from packaging.version import Version
 from pytest_check import check
 
-from idefix_cli.__main__ import main
+from idefix_cli.__main__ import idfx_entry_point as main
 from idefix_cli._commands.conf import substitute_cmake_args
 
 
diff --git a/tests/test_digest.py b/tests/test_digest.py
index c06f901..f177868 100644
--- a/tests/test_digest.py
+++ b/tests/test_digest.py
@@ -5,7 +5,7 @@
 
 import pytest
 
-from idefix_cli.__main__ import main
+from idefix_cli.__main__ import idfx_entry_point as main
 from idefix_cli._commands.digest import command as digest
 
 if sys.version_info >= (3, 11):
diff --git a/tests/test_read.py b/tests/test_read.py
index 0f5ec6e..5ac1108 100644
--- a/tests/test_read.py
+++ b/tests/test_read.py
@@ -2,7 +2,7 @@
 
 from pytest_check import check
 
-from idefix_cli.__main__ import main
+from idefix_cli.__main__ import idfx_entry_point as main
 
 
 def test_read_not_a_file(tmp_path, capsys):
diff --git a/tests/test_run.py b/tests/test_run.py
index 0e26d69..ee33072 100644
--- a/tests/test_run.py
+++ b/tests/test_run.py
@@ -1,6 +1,6 @@
 import pytest
 
-from idefix_cli.__main__ import main
+from idefix_cli.__main__ import idfx_entry_point as main
 from idefix_cli._commands.run import get_highest_power_of_two
 
 
diff --git a/tests/test_ux.py b/tests/test_ux.py
index 598e6e4..1c74f12 100644
--- a/tests/test_ux.py
+++ b/tests/test_ux.py
@@ -1,7 +1,7 @@
 import pytest
 from pytest_check import check
 
-from idefix_cli.__main__ import main
+from idefix_cli.__main__ import idfx_entry_point as main
 
 HELP_MESSAGE = (
     "usage: idfx [-h] [-v] {clean,clone,conf,digest,read,run,switch,write} ...\n"
diff --git a/tests/test_write.py b/tests/test_write.py
index 3640f43..aadfbbd 100644
--- a/tests/test_write.py
+++ b/tests/test_write.py
@@ -6,7 +6,7 @@
 import pytest
 from pytest_check import check
 
-from idefix_cli.__main__ import main
+from idefix_cli.__main__ import idfx_entry_point as main
 
 jq_available = subprocess.run(["which", "jq"]).returncode == 0